Automatic setting tool

Abstract

A fastener setting tool is disclosed for setting, to a panel member or the like, a fastener including an internally threaded nut portion, a tubular portion extending from the nut portion and a flange portion at the end of the tubular portion. The tool has a driving shaft, a nut member operatively connected to the shaft, a pulling rod threadably connected to the nut member and extending forward to the tool and a mandrel movably mounted to the end of the pulling rod with the end thereof having an externally threaded portion, and a half nut connected to the nut member so as to be rotated with the nut member and mounted on the externally threaded surface of the pulling rod under a predetermined binding force by a ring. The mandrel of the fastener setting tool is furthermore independently slidable with respect to the pull rod and is furthermore associated with a stop clutch which engages the mandrel when pushed back by a blind nut type of fastener so as to prevent further rotation.

What is claimed is: 
     
       1. A fastener setting tool for setting, to a panel member or the like, a fastener including an internally threaded nut portion, a tubular portion extending from said nut portion and a flange portion at the end of said tubular portion, said tool comprising a driving shaft, a nut member operatively connected to said shaft, a pulling rod threadably connected to said nut member and extending forward to said tool and a mandrel removably mounted to the end of said pulling rod with the end thereof having an externally threaded portion, a half nut connected to said nut member so as to be rotated with said nut member and mounted on the externally threaded surface of said pulling rod under a predetermined binding force by a ring. 
     
     
       2. The setting tool of claim 1 wherein said driving shaft is operatively connected to said nut member through a first clutch consisting of two elements, one of which can be axially slid on and rotated together with the driving shaft and the other being mounted opposite to said one element so as to be rotated together with said nut member, and said first clutch is formed in a manner that, when a predetermined anti-rotating force is applied to said nut member during rotation of the driving shaft, said one of the clutch elements is slid on the engagement surface of the other while generating a click therebetween. 
     
     
       3. The setting tool of claim 1 or 2 including a second clutch consisting of second clutch elements located between said pulling rod and a housing of the tool body and disposed so as to bring said second clutch elements into engagement with each other only when the tool is moved toward the panel member. 
     
     
       4. The setting tool of claim 3 wherein said second clutch includes a first element connected to said pulling rod through a pin passing through an elongated slit on an end portion of said pulling rod, and a second element slidably mounted on the outer surface portion of said pulling rod rearward to said first element through a pin extending into an elongated slit of said housing formed as a key groove. 
     
     
       5. The setting tool of claim 4 including a first spring for biasing said first element of said second clutch toward the end of said pulling rod, and a second spring for biasing said second element toward a nose of the tool. 
     
     
       6. The setting tool of claim 4 wherein said first and second elements of said second clutch have such teeth that, during rotation of said pulling rod, both the elements when partially engaged with each other begin sliding engagement above a predetermined torque but when fully engaged, maintain the engagement even when the torque greater than said predetermined value is applied. 
     
     
       7. The setting tool of claim 4 wherein said first and second elements of said second clutch have such teeth that, when both the elements are fully engaged with each other during reverse rotation of said pulling rod to which a torque greater than a predetermined value is applied, the elements are slid on their surfaces to generate a click. 
     
     
       8. The setting tool of claim 3 wherein said mandrel has a rear end mounted to the end of said pulling rod to be slid but not rotated with respect to said pulling rod. 
     
     
       9. A blind rivet nut setting tool comprising a housing having a nose piece for engagement with the head of a rivet, a pull bar rotatably and axially reciprocably mounted in the housing, a friction nut in mesh with an external thread of the pull bar so that rotation of the nut results in rotation of the pull bar up to the limit of said friction and in retraction of the pull bar when such limit is exceeded, power operated means for rotating the nut, a mandrel coupled to rotate with the pull bar but reciprocable relative thereto, and a clutch member non-rotatable in the housing but axially retractable against spring pressure by which it is normally held in a forward position against stop means of the housing, the clutch member when in its forward position being lockingly engaged upon retraction of the mandrel by a complementary member adjacent the mandrel, which is normally held by spring means in an advanced position out of engagement with the clutch member, retraction of the mandrel when bringing together the nose piece and a rivet threaded a short way along the mandrel thus resulting in the mandrel becoming locked against rotation by engagement with the clutch member and consequently the limit of said friction being exceeded and setting of the rivet being initiated. 
     
     
       10. A tool according to claim 9 in which the mandrel is threaded for only a short distance from its tip to limit approach of the rivet towards the nose piece when it is initially threaded on the mandrel. 
     
     
       11. A tool according to claim 10 in which the nose piece is adjustable axially on the housing.